/Engine/Plugins/Online/OnlineSubsystemSteam/Source/Public/OnlineAuthInterfaceUtilsSteam.h
If you would like to receive analytics as to the success/failure for users we can identify (have their unique net id), use the result delegate instead.
typedef TMulticastDelegate_OneParam< void, const class [FUniqueNetId](API\Runtime\CoreOnline\Online\FUniqueNetId) & > FOnSteamAuthFailure